Aerosol spray container and filter



Oct. 5, 1965 M. E. WEBSTER 3,209,954

AEROSOL SPRAY CONTAINER AND FILTER Filed Nov. 7, 1963 2 Sheets-Sheet lINVENTOR MILO E. WEBSTER BY 75% p qfl g m Spr ATTORN Y5 Oct. 5, 1965 E.WEBSTER AEROSOL SPRAY CONTAINER AND FILTER 2 Sheets-Sheet 2 Filed Nov.7, 1963 a a J INVENTOR M/LO E. WEBSTER DMZ? %EY$ button operation.

United States Patent 3,209,954 AEROSOL SPRAY CONTAINER AND FILTER MiloE. Webster, Rochester, N.Y., assignor to Bernz O Matic Corporation,Rochester, N.Y., a corporation of New York Filed Nov. 7, 1963, Ser. No.322,229 11 Claims. (Cl. 222-189) This invention relates to an improvedaerosol spray container.

Various fluids, such as, for example, paints, insecticides, cleaners,deodorants, and the like are marketed in aerosol spray containers whichpermits their despensing and use as a fine aerosol spray.

The aerosol spray container generally comprises a pressurized container,as for example, a cylinder or can having therein the fluid to bedispensed and a propellant under pressure. A dip tube extends below thesurface of the fluid and terminates at the bottom portion of thecontainer and an aerosol spray valve, generally of the push-button type,is flow connected with the dip tube so that upon opening of the valve,as for example, by push-button operation, the pressure of the propellantforces the fluid from the container up through the dip tube and outthrough the aerosol valve in the form of a fine spray. The aerosol sprayvalve is provided with a terminal orifice which acts as the spray nozzleand is generally additionally provided with a primary orifice which isnormally sealed but which becomes exposed, acting as the valve uponpush- The orifices are in the form of constrictions having diameterswhich generally are larger than .020", as for example, between 0.20 and.040.

A major problem encountered in connection with the aerosol containers isthe tendency of the aerosol valve to become plugged. This isparticularly troublesome in connection with the dispensing of paint, andsimilar materials, but is also a problem in connection with thedispensing of other fluids. The plugging is generally caused by foreignparticles or over-sized particles built up from the material beingsprayed which sink to the bottom of the container and which are forcedup the dip tube with the material being dispensed clogging one of theorifice constrictions in the aerosol spray valve. These particles whichplug the orifice or orifices of the spray valve are firmly held in placeby the pressure differential so that the plugging cannot be readilycorrected and the container is rendered inoperative preventing furtherdispensing and use of the contents and resulting in severe customerdissatisfaction.

One object of this invention is a construction which reliably avoids theabove-mentioned disadvantage in a simple and economical manner.

This and still further objects will become apparent from the followingdescription read in conjunction with the accompanying drawing wherein:

FIG. 1 is an elevation view in cross-section showing an aerosoldispenser according to the invention; and

FIG. 2 is an elevation view of an insert for use in an aerosol containeraccording to the invention;

FIG. 3 is a bottom view of the insert shown in FIG. 2;

FIG. 4 and FIG. 5 are fragmentary views of a container as is shown inFIG. 1, and showing alternative forms of construction for the containerparts.

In the drawings like reference characters indicate corresponding parts.

In accordance with the invention, the plugging of aerosol valves isprevented by installing an insert in the conduit provided for conveyingfluid to the orifice restriction in the valve (and which can be made upof a number of elements such as a dip tube, valve inlet and internalvalve passageways). The insert effects a straining of the fluid3,209,954 l atented Oct. 5, 1965 to prevent particles as would constrictthe orifice from passing to the orifice. The insert is a solid piecedisposed in close fitting relation with the walls of the conduit and thesurface of the insert confronting the wall of the conduit has aplurality of axially extending grooves providing a like number ofaxially extending passageways each defined by one of the grooves and theoverlying portion of the conduit. The passageways are smaller than thevalve orifice constriction, so that the desired straining can beeffected. The insert can be in integral part of the valve or can be aseparate part suitably inserted in some part of the conduit, such as ina dip tube or in one of the valve passageways.

The grooves in the insert, conveniently, are rectangular having a depthdimension extending radially and a width dimension extendingcircumferentially. The smaller of said dimensions is preferably about20% smaller than the diameter of the smallest orifice constriction ofthe valve. Commonly the smallest of said dimensions is desirably betweenabout 0.010" and 0.015. The smallest orifice constriction is commonlyabout 0.020 diameter. These dimensions find particular application inthe case of paint.

Referring to the embodiment shown in FIG. 1, 1 represents thepressurized container which in the embodiment shown is in the form of analuminum cylinder, though any known or conventional container, as forexample, the conventional tin cans may be used. The opening at the upperend of the container is seal-ed by the conventional crimped sealing cap2 which is provided with the aerosol spray valve having the plasticpush-button spray head 3 provided with the terminal spray orifice 4, theintermediate expansion chamber 5, and the primary orifice 6. The primaryorifice 6 consists of a lateral hole extending through the wall of thestem portion 7 in communication with the intermediate expansion chamber5. The aerosol spray valve is also provided with the hollow metalhousing 8 joined by crimping to the cap 2. The housing 8 contains thespring 9 and the spring plunger 10 which is connected to the stem 7 ofthe spray button. The stem 7 extends through a central hole in the cap 2provided with the gasket 11. The spring 9 normally forces the plunger 10upward so that its upper edge contacts the gasket 11, and the primaryorifice 6 is sealed by the gasket 11. When the spray button 3 isdepressed, the spring 9 is compressed, and the primary orifice 6exposed. Pressed into the lower end of the housing 8 is the dip tube 12which can be formed of plastic material, as for example, polyethylene,polyvinylchloride or the like. The dip tube 12 extends to the bottom ofthe container 1 in the conventional manner, and as shown to thelowermost forward corner of the container.

The container 1 contains the liquid 15 to be dispensed,-

as for example, the paint, and is additionally charged with a propellentas for example liquefied propane, the propane vapor filling andpressurizing the upper space at 16. A conventional agitator ball orballs, for example, the glass agitator ball 17 is also provided in thecontainer to aid the mixing of the paint by shaping prior to use.

In operation, the container is shaken and the agitator ball 17 aids inmixing the paint which generally consists of pigments, vehicle solidssuch as resin, and solvent. The terminal orifice 4 is then pointed atthe surface to be coated and the spray head 3 depressed. The downwardmovement of the spray head 3 exposes the primary orifice 6 and causesdownward movement of the plunger 10 and compression of the spring 9.

The pressure of the propellent vapor forces the paint up through the diptube 12 past the plunger 8, which is provided with suitable clearance oropenings for this purpose, through. the primary orifice 6 into theexpansion chamber and out through the terminal orifice 4 in the form ofa fine spray which is used to coat the surface.

Upon release of the spray head 3, the action of the spring 9 in theconventional manner forces the spray head 3 upwardly so that the orifice6 is masked by the gasket 11 shutting off the spray.

Normally, if a foreign particle were present in the paint, as forexample a flake of aluminum in connection with aluminum containers or apiece of oxidized steel in connection with steel containers, or anagglomeration of pigment particles, or over-sized pigment particles orthe like, the same, after sinking to the bottom of the container wouldbe forced through the dip tube 12 clogging either the primary orifice 6and/or the terminal orifice 4- rendering the container inoperative. Thedifferential pressure would lock such particle in place over or in theorifice in question so that the situation could not be readily remediedexcept for example by exchanging the spray head.

In accordance with the invention, an insert 20, shown in detail in FIGS.2 and 3, is utilized to prevent clogging of the valve. The insert is anelongated, solid piece of plastic such as polyethylene, desirably lowpressure polyethylene, having a plurality of axially extending grooves21. The insert 26, as shown in FIG. 1, is installed in the lower end ofthe dip tube 12, wherein it is received as a press fit and is disposedin tight fitting relation with the wall of the dip tube 12.

In the embodiment shown in FIG. 4, the valve includes a plastic housing22 which is crimped in place in the cap 2 to secure the valve on thecontainer. The valve includes, as an integral part of the plastichousing 22, the insert 24. The end of dip tube 12 is slid over theinsert to provide the insert in the conduit from the fluid in thecontainer to the valve, all to provide straining action of the insertaccording to the invention.

In the embodiment shown in FIG. 5, the insert as well as the confrontingconduit wall portion, which with the slots in the insert define thepassageways provided for straining, are included as parts of the valveassembly. The valve is provided with an insert 24 as an integral partthereof, just as in the case of the embodiment shown in FIG. 4. Further,however, the valve is outfitted with the nipple 25 which is in tightfitting relation with the insert 24, the inside walls of the nipple 25overlying the grooves 21 so as to provide passageways for straining. Thedip tube 12 is slid over the nipple 25 and is secured thereon by theenlargement 26 of the nipple.

With the construction in accordance with the invention, a particle aswould tend to plug or clog an orifice constriction of the valve wouldmerely become wedged against an entrance to a groove 21 and would notinterfere with operations as paint or other fluid could be forcedthrough the other grooves 21. Any particle passing through a groove 21could not clog in the orifices 6 or 4 as these latter orifices are of alarger size than the perforations 14. In the embodiment shown in FIG. 1,even if all the grooves 21 become covered by foreign particles, thiswould not present a serious problem as further agitation and the actionof the agitator ball would dislodge such particles so that the containercould be rendered again operative. Commonly, a lodged particle,regardless of the position of the insert 21 will become dislodgedbecause of pressure equalization across the insert.

The inside diameter of the conduit in which the insert is installed canbe about and the insert can be of somewhat greater diameter to provide apress fit. About 2i) grooves can be formed in the insert.

Advantages of construction according to the invention include low costand dependability. Further the construction can be incorporated into theconstruction of existing or previously known parts of the container orit can be merely added to known container parts, such as by merelyplacing the insert in the dip tube.

The improvement in accordance with the invention is, of course,applicable in connection with any of the known or conventional aerosolspray containers provided with any of the known or conventional aerosolspray valves and charged with any of the conventional aerosol materials,and conventional propellents, as for example, fluorinated hydrocarbon,such as the various freons used for this purpose.

While the invention has been described in detail with reference tospecific embodiments shown, various changes and modifications which fallwithin the spirit of the invention and scope of the appended claims willbecome apparent to the skilled artisan. The invention, therefore, isonly intended to be limited by the appended claims or their equivalentswherein I have endeavored to claim all inherent novelty.

What is claimed is:

1. In an aerosol spray container comprising a pressurized containerhaving therein a fluid to be dispensed and a propellent under pressure,a valve for discharge of fluid from the container mounted on thecontainer, said valve having at least one orifice constriction, aconduit for conveying fluid from within the container to the orificeconstriction for passage therethrough, the improvement which comprises asolid insert positioned in said conduit in close fitting relation withthe walls thereof, the surface of the insert confronting the conduitwall having a plurality of axially extending grooves providing a likenumber of axially extending passageways each defined by one of saidgrooves and the overlying portion of the conduit and communicating theportion of the conduit on one side of the insert with the portion of theconduit on the other side of the insert, said passageways being smallerthan said orifice for straining the fluid to prevent particles as wouldconstrict said orifice from passing to the orifice.

2. Improvement according to claim 1, wherein said conduit includes avalve inlet and a dip tube having one end thereof communicating with thevalve inlet and the other end thereof communicating with the fluid inthe container, said insert being disposed in said dip tube.

3. Improvement according to claim 1, wherein said insert is integralwith the valve housing.

4. In an aerosol spray container comprising a pressurized containerhaving therein a fluid to be dispensed and a propellent under pressure,a valve for discharge of fluid from the container mounted on thecontainer and having a valve inlet disposed within the container forreceiving fluid from the container, said valve having at least oneorifice constriction, a dip tube within the container having one endthereof in flow communication with the said valve inlet and the otherend thereof disposed below the surface of the fluid in the container forreceiving the fluid for conveyance to the valve inlet, the improvementwhich comprises an insert disposed in said clip tube in tight fittingrelation with the walls thereof, the surface of the insert confrontingthe dip tube having a plurality of axially extending grooves providing alike number of axially extending passageways each defined by one of saidgrooves and the overlying portion of said tube and communicating theportion of the dip tube on one side of the insert with the portion ofthe dip tube on the other side of the insert, said passageways beingsmaller than said orifice for straining the fluid to prevent particlesas would constrict said orifice frompassing to the orifice.

5. Improvement according to claim 4 in which said aerosol spray valvehas a primary and terminal orifice and in which saidperforations aresmaller than both said orifices.

6. Improvement according to claim 4 in which said fluid is paint.

7. Improvement according to claim 4, said passageways having a depthdimension extending radially and a width dimension extendingcircumferentially, the smaller of said dimensions being between about0.010 and 0.015".

8. Improvement according to claim 6, said passageways having a depthdimension extending radially and a width dimension extendingcircumferentially, the smaller of said dimensions being between about0.010 and 0.015".

9. Improvement according to claim 8 wherein the smallest orificeconstriction in the valve being greater than about 0.020" diameter.

10. In an aerosol spray container having a dip tube in flowcommunication wtih a discharge opening from the container, theimprovement comprising an insert disposed in said dip tube in tightfitting relation with the walls thereof, the surface of the insertconfronting the dip tube having a plurality of axially extending groovesproviding a like number of axially extending passageways each defined byone of said grooves and the overlying portion of said tube andcommunicating the portion of the dip tube on one side of the insert withthe portion of the dip tube on the other side of the insert, the saidpassageways being of a smaller size than the smallest cross-sectionalsize of the flow path from the dip tube through the discharge opening.

11. Improvement according to claim 10, wherein the dip tube isexpansible and the insert press fit therein and the tube elasticallygrips the insert and prevents displacement thereof.

References Cited by the Examiner UNITED STATES PATENTS 1,964,218 6/34Schargorodsky 23986 2,376,231 5/45 Cohn 222189 X 2,774,628 12/56Engstrum 222189 2,815,889 12/57 Stetz et al 222-189 3,098,589 7/63Graham 222189 X 3,129,730 4/64 Simon 222-189 X LOUIS J. DEMBO, PrimaryExaminer.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No,3,209,954 October S, 1965 Milo E. Webster It is hereby certified thaterror appears in the above numbered patent requiring correction and thatthe said Letters Patent should read as corrected below.

Column 1, line 32, for "0.20 and .040 read .020 and .040--; column 5,line 11, for "wtih" read with Signed and sealed this 23rd day of August1966.

(SEAL) Attest:

ERNEST W. SWHJER EDWARD J. BRENNER Attesting Officer Commissioner ofPatents

10. IN AN AEROSOL SPRAY CONTAINER HAVING A DIP TUBE IN FLOWCOMMUNICATION WITH A DISCHARGE OPENING FROM THE CONTAINER, THEIMPROVEMENT COMPRISING AN INSERT DISPOSED IN SAID DIP TUBE IN TIGHTFITTING RELATION WITH THE WALLS THEREOF, THE SURFACE OF THE INSERTCONFRONTING THE DIP TUBE HAVING A PLURALITY OF AXIALLY EXTENDING GROOVESPROVIDING A LIKE NUBMER OF AXIALLY EXTENDING PASSAGEWAYS EACH DEFINED BYONE OF SAID GROOVES AND THE OVERLYING PORTION OF SAID TUBE ANDCOMMUNICATING THE PORTION OF THE DIP TUBE ON ONE SIDE OF THE INSERT WITHTHE PORTION OF THE DIP TUBE ON THE OTHER SIDE OF THE INSERT, THE SAIDPASSAGEWAYS BEING OF A SMALLER SIZE THAN THE SMALLEST CROSS-SECTIONALSIZE OF THE FLOW PATH FROM THE DIP TUBE THROUGH THE DISCHARGE OPENING.